midas-nx-mcp

A local MCP server that lets Claude (and other MCP clients) read the model open in MIDAS Gen NX or MIDAS Civil NX, and change it only through steps you see and confirm first. Built on the midas-nx SDK.

Personal, employee-led project; not an official MIDAS IT product.

Status: alpha. Verified live on Gen NX 2026 and Civil NX 2026 on small test models (see PLAN.md); not yet used on large production models.

사용 설명서 (한국어): docs/user_guide_ko.md

What you can ask

• "Summarise the Gen model." - node, element, material, section, load case counts
• "Show the DL reactions." - result tables after an analysis
• "Show me the model." - a picture of the NX window
• "Which design code is set?" - design parameter tables
• "Add a node at (4, 3, 0)", "Run the analysis" - previewed, applied only after you agree

Requirements

• Windows, with Gen NX or Civil NX running on the same PC and its Open API connected (Apps > API Settings)
• A MAPI key per product (Apps > API Settings in each program). Keys differ between Gen and Civil, and a wrong key still reports "connected", so do not swap them.
• uv (installs Python and the server for you); not needed for the Claude Desktop bundle below

Install

Claude Desktop - one click

Download midas-nx-mcp-<version>.mcpb from the latest release and open it (or drag it onto Settings > Extensions). Claude Desktop installs Python and the server itself, and asks for your Gen and Civil keys; leave the one you do not use empty. Change them later under Settings > Extensions.

Claude Desktop - by hand

Settings > Developer > Edit Config (not "Add custom connector": that is for remote servers) and add:

{
  "mcpServers": {
    "midas-nx": {
      "command": "uvx",
      "args": ["midas-nx-mcp"],
      "env": {
        "MIDAS_MAPI_KEY_GEN": "your Gen NX key",
        "MIDAS_MAPI_KEY_CIVIL": "your Civil NX key"
      }
    }
  }
}

Quit Claude Desktop completely (tray icon too) and start it again. Settings > Developer should show midas-nx as running.

Claude Code

claude mcp add midas-nx -e MIDAS_MAPI_KEY_GEN=your-gen-key -- uvx midas-nx-mcp

Other clients (Codex, ...)

Add a STDIO server with command uvx, argument midas-nx-mcp, and the environment variables below.

Settings

Tools

Reading (nothing in the model changes):

Changing - each is called twice: first a preview with a confirm_token, then the same call with that token. It applies only if nothing changed in between, and reads the table back afterwards:

Any write discards the analysis results in NX (even one that stores the same value); run the analysis again before reading results.

Never exposed: new/open/import document, emptying a table.

Development

git clone https://github.com/Dennis5882/midas-nx-mcp
cd midas-nx-mcp
python -m venv .venv
.venv\Scripts\activate
pip install -e ".[dev]"
copy .env.example .env      # a checkout reads its .env; an installed package does not
pytest
ruff check src tests scripts
npx @modelcontextprotocol/inspector .venv\Scripts\python.exe -m midas_nx_mcp.server

AGENTS.md holds the safety rules every tool follows, and PLAN.md what has been verified live and what is open.

License

MIT